Throughout the years, researchers have tried to understand dynamics and general patterns associated with human movement, e.g. in the context of urban planning, to improve the lives of citizens. To do this, it is necessary to properly analyse the spatio-temporal and the thematic properties of their trajectory data. Thematic maps, particularly 2D maps and 3D space-time cubes (STCs), are among the most common approaches to analyse and visualize these data. Previous research attests to the usefulness of these visualization techniques in different types of tasks. However, it is unlikely that the analysis of trajectories will be always limited to a specific type of task, thus, motivating additional studies to evaluate the dis/advantages of combining both techniques, within the same view/interaction context. In this paper, we address this specific challenge, by presenting a comparative study between three prototypes, one using a 2D map, one using a STC, and one combining both techniques, for the visualization of trajectories. Our results support previous studies' conclusions, by showing the advantages of 2D maps and STCs for spatial and spatio-temporal tasks, respectively. They also point out towards the advantages of using both techniques together, as users seem to prefer this alternative and are able to complete different types of tasks accurately, despite the increasing complexity of the visualization.